A wellhead blowout preventer type polish rod seal

Abstract

The utility model discloses a wellhead blowout preventer formula polished rod seal ware, it includes the polished rod, is equipped with the blowout preventer device from top to bottom in proper order on the polished rod, the packing seal device of being able to seal polished rod and the rubber seal device of being able to seal polished rod, the rubber seal device is equipped with the polished rod centralizer of being able to right polished rod down, blowout preventer device, packing seal device, rubber seal device between screw thread connection, be equipped with trapezoidal oil receiving groove on blowout preventer device, blowout preventer device includes the blowout preventer pressure cap around polished rod, is equipped with the chamber around polished rod setting in blowout preventer pressure cap, install blowout preventer ball in the chamber, blowout preventer pressure cap is equipped with the spring and the baffle of being able to press from inside to prevent blowout preventer ball, the diameter of blowout preventer ball is greater than the diameter of polished rod. The utility model has the advantages of avoiding the environmental pollution caused by the spatter of petroleum, avoiding the leakage of petroleum, improving the service life, facilitating replacement and maintenance etc.

Description

Technical Field

[0001] This utility model relates to the field of oil production equipment technology, specifically a wellhead blowout preventer polished rod seal. Background Technology

[0002] Currently, oil pumping units are widely used for oil extraction in China. These units contain a polished rod that moves back and forth in a linear motion, drawing oil up through this motion. During extraction, oil rises from the bottom of the well to the wellhead and flows out through the tubing. To prevent oil from leaking out of the polished rod and causing pollution, a sealant is typically placed there. These sealants usually use packing seals. However, during use, the polished rod is prone to tilting and corrosion, and misalignment can occur between the sealant, the polished rod, and the wellhead. In severe cases, this can lead to polished rod breakage. If the broken rod falls under the sealant, a mixture of oil, gas, and water will spray out from the top of the sealant, causing environmental pollution, oil waste, and complications for subsequent cleanup and operations. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a wellhead blowout preventer for polished rods that can ensure sealing and prevent oil splashing after the polished rod breaks.

[0004] To solve the above-mentioned technical problems, this utility model includes a smooth rod, characterized by the following structural features: The smooth rod is provided with, from top to bottom, a blowout preventer, a packing seal for sealing the smooth rod, and a rubber seal for sealing the smooth rod. Below the rubber seal is a smooth rod straightener for maintaining the smooth rod's alignment. The blowout preventer, packing seal, and rubber seal are threaded together. The blowout preventer has a trapezoidal oil receiving groove. The blowout preventer includes a blowout preventer cap surrounding the smooth rod, a slide rail inside the blowout preventer cap, a blowout preventer ball installed in the slide rail, and a spring inside the blowout preventer cap that can press the blowout preventer ball inward. A baffle is installed on one side of the spring to press the blowout preventer ball. The diameter of the blowout preventer ball is larger than the diameter of the smooth rod.

[0005] With the above structure, the trapezoidal oil receiving groove at the top can catch leaked oil, preventing oil pollution to the environment and facilitating collection. The blowout preventer blocks oil from spraying out after the polished rod breaks. The polished rod is sealed by the packing seal and rubber seal, ensuring its sealing. The polished rod centralizer maintains the angle of the polished rod. When the polished rod breaks, it falls, and the blowout preventer ball, no longer blocked by the polished rod, is squeezed inward by the compressed spring. Due to the rapid diffusion of formation pressure, the pressure in the downhole tubing is greater than atmospheric pressure. Under the influence of atmospheric pressure, the blowout preventer ball will get stuck in the hole through which the polished rod passes in the blowout preventer cap, playing a role in sealing and preventing blowout, thus preventing oil leakage. The diameter of the blowout preventer ball is larger than the diameter of the polished rod to prevent the blowout preventer ball from falling, ensuring the sealing effect. In this way, the combination of the blowout preventer and the two-stage sealing device ensures the sealing of the polished rod while preventing its breakage, thus ensuring its service life.

[0006] The packing sealing device includes a ball-head fastening sleeve surrounding the polished rod. A ball-head assembly is installed inside the ball-head fastening sleeve. The bottom of the ball-head assembly includes a rotatable universal ball head and a sealing tube located at the upper end of the universal ball head. The top of the ball-head assembly is threadedly connected to the blowout preventer cap. The ball-head assembly has a hollow structure and an annular groove. Packing is installed in the annular groove. A barrier is installed above the packing to seal the packing. The universal ball head can rotate within the ball-head fastening sleeve. After rotation, the direction of the ball-head assembly can be adjusted to ensure that the angle between the ball-head assembly and the polished rod is consistent, avoiding pressure and wear on the polished rod and protecting it to the greatest extent. At the same time, the packing installed inside the ball-head assembly and the barrier pressing on the upper end of the packing compress the packing. The packing adheres to and compresses the polished rod, sealing it and forming a sealing structure. This prevents the polished rod from carrying more oil upwards, protecting the polished rod while ensuring a good seal.

[0007] The rubber sealing device includes a push-pull rod fixing cap arranged around the polished rod. The push-pull rod fixing cap is fitted with rubber surrounding the polished rod. The push-pull rod fixing cap has two cylinders extending radially outward, which are symmetrically arranged. Inside the cylinders are push blocks that can move along the cylinders. After the push blocks move, they can squeeze the rubber. Through the movement of the push blocks, the rubber is squeezed inward and pressed against the polished rod to achieve a rubber seal. After the rubber seal is completed, it can close the lower space, cut off the upward pressure transmission from the wellhead, and facilitate the installation or replacement of the upper structure, as well as the replacement of the packing.

[0008] The outer end of the push block is connected to a push rod, which passes through the outer end face of the cylinder. The outer end of the push rod is connected to a semi-straight handle that can drive the push rod to move. The semi-straight handle makes it convenient for the operator to hold.

[0009] The blowout preventer cap is provided with a pipe wrench force groove on its outer side.

[0010] The universal ball joint is an elliptical ball. The elliptical shape limits the rotation angle of the universal ball joint, preventing large-angle tilting of the ball joint assembly, facilitating installation, and improving the efficiency of the rod.

[0011] The packing is made of fluororubber, which has good high temperature resistance and corrosion resistance, effectively resisting corrosion from petroleum hydrocarbons and improving service life.

[0012] In summary, this utility model has the advantages of avoiding environmental pollution caused by oil splashing, preventing oil leaks, increasing service life, and facilitating replacement and maintenance. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model;

[0014] Figure 2 This is a schematic diagram of the structure of this utility model after the bare rod breaks. Detailed Implementation

[0015] like Figure 1 , 2 As shown, this utility model includes a polished rod 1, on which a blowout preventer, a packing seal, and a rubber seal are sequentially mounted from top to bottom. The blowout preventer and the packing seal are connected by threads, as are the packing seal and the rubber seal. A trapezoidal oil collection groove 2 is provided at the upper end of the blowout preventer. When the polished rod 1 moves up and down, the oil carried out is collected through the trapezoidal oil collection groove 2, preventing leakage. The trapezoidal shape is designed with inclined sides, which guide the oil to the bottom of the oil collection groove, ensuring smooth and continuous oil collection, preventing oil contamination, and preventing oil from being carried back into the packing seal or the rubber seal, thus avoiding mutual wear between the polished rod 1 and the sealing devices.

[0016] like Figure 1 , 2As shown, the blowout preventer includes a blowout preventer cap 34 surrounding the polished rod 1. A slide 35 is provided inside the blowout preventer cap 34, and a blowout preventer ball 31 is installed within the slide 35. The diameter of the blowout preventer ball 31 is larger than the diameter of the polished rod 1. A spring 32 and a baffle are installed within the slide 35. A bolt 33 is installed at the radial outer end of the slide 35, fixing one end of the spring 32. The spring 32 and one end of the baffle press against the blowout preventer ball 31. When the polished rod 1 moves up and down, the blowout preventer ball 31 presses against the polished rod 1 and the spring 32 and baffle. When the polished rod 1 breaks and falls, the pressure inside the pipe is greater than atmospheric pressure. The spring 32 pushes the blowout preventer ball 31 inward, and the blowout preventer ball 31 presses against the hole in the polished rod 1 of the blowout preventer cap 34. The oil and gas pressure inside the pipe presses the blowout preventer ball 31 against the hole in the polished rod 1, preventing oil from splashing upward. By stabilizing the pressure inside the pipe, environmental pollution caused by oil leakage is avoided, and oil waste is prevented. The blowout preventer cap 34 has a pipe wrench force groove 4 on its outer side, which facilitates the gripping of the pipe wrench and the installation of the blowout preventer.

[0017] like Figure 1 , 2 As shown, the packing sealing device includes a ball-head fastening sleeve 54 surrounding the guide rod 1, and a ball-head assembly 53 is provided inside the ball-head fastening sleeve 54. The ball-head assembly 53 includes a universal ball head at the lower end and a sealing tube at the upper side. The upper end of the sealing tube extends upward into the blowout preventer cap 34. The connection between the packing sealing device and the blowout preventer is achieved through the threaded connection between the ball-head assembly 53 and the blowout preventer cap 34. The universal ball head is an elliptical ball, and the elliptical shape limits the rotation angle of the universal ball head, preventing large-angle skew of the ball-head assembly 53, facilitating installation, and improving installation efficiency. The universal ball head and the blowout preventer cap 34 are connected by threads. A hollow structure is provided inside the ball-head assembly 53, through which the guide rod 1 passes. An annular groove is provided inside the sealing tube, and a packing 52 surrounding the guide rod 1 is installed in the annular groove. In this embodiment, the packing 52 is made of fluororubber; in other embodiments, nitrile rubber can also be used. Fluororubber packing 52 exhibits good high-temperature and corrosion resistance, thus extending its service life. Nitrile rubber, on the other hand, possesses excellent oil and heat resistance, effectively preventing oil molecule penetration and ensuring sealing efficiency and service life. A spacer 51 is installed at the top of the ball joint assembly 53 to press against the packing 52. The spacer 51 is located at the top of the ball joint assembly 53, with its lower surface pressing against the upper surface of the packing 52, ensuring the packing 52 is tight and thus guaranteeing its sealing effect.

[0018] like Figure 1 , 2As shown, the rubber sealing device includes a rubber sheet 61 surrounding the smooth rod 1. A push-pull rod fixing cap 64 is provided outside the rubber sheet 61, and the upper end of the push-pull rod fixing cap 64 is threadedly connected to the ball head fastening sleeve 54. Two cylinders 65 extending radially outward along the smooth rod 1 are provided inside the push-pull rod fixing cap 64. Each cylinder 65 has a cavity, and the two cylinders 65 are symmetrically arranged. A push block 62 that can move radially is provided inside the cylinder 65. When the push block 62 moves inward, it can compress the rubber sheet 61, thereby ensuring the rubber sheet 61 compresses the smooth rod 1 and ensuring the sealing performance of the rubber sheet 61. A push rod is connected to the outside of the push block 62, extending outward to the outside of the cylinder 65. A handle for moving the push rod is installed at the outermost end of the push rod. In this embodiment, the outer surface of the push rod is threaded, and the push rod is threadedly connected to the outer end face of the cylinder 65. When the handle drives the push rod to rotate, the rotational motion is converted into linear motion, thereby changing the position of the push rod inside the cylinder 65. In this embodiment, the handle 63 is a semi-inline handle 63. The length of the handle 63 is only half the height of the cylinder 65 and is located on one side of the push rod, forming a semi-inline shape. The semi-inline handle 63 is convenient for the operator to hold and rotate, and the rubber 61 achieves the sealing of the smooth rod 1.

[0019] like Figure 1 , 2 As shown, when the packing 52 needs to be replaced, the semi-straight handle 63 is rotated, and the pusher block 62 is moved by the push rod, thereby tightly fitting the rubber 61 and the polished rod 1 together. After fitting, the rubber 61 seals the space under the polished rod 1, cutting off the upward pressure transmission from the wellhead. Then, the packing 52 inside the universal ball head can be easily replaced, improving the replacement efficiency of the packing 52 and ensuring the sealing quality. At the same time, the angle of the universal ball head can be adjusted according to the position and angle of the polished rod 1. After the angle of the polished rod 1 is consistent with the angle of the sealing device, the sealing device achieves step-by-step sealing. The ball head fastening sleeve 54 can be easily adjusted, reducing wear and improving efficiency.

[0020] like Figure 1 , 2 As shown, the lower end of the push-pull rod fixing cap 64 is provided with a long hoop 71, and a pressure reducer is installed inside the long hoop 71. The pressure reducer reduces the oil pressure brought into the sealing device by the polished rod 1, avoiding impact on the sealing device. A polished rod straightener 8 is installed on the polished rod 1 to ensure the direction of the polished rod 1 and prevent the direction of the polished rod 1 from deviating. This ensures the service life of the sealing device.

Claims

1. A wellhead blowout preventer polished rod seal, comprising a polished rod (1), characterized in that: The polished rod (1) is provided with a blowout preventer, a packing seal device that can seal the polished rod (1), and a rubber seal device that can seal the polished rod (1) in sequence from top to bottom. The polished rod straightener (8) that can straighten the polished rod (1) is provided below the rubber seal device. The blowout preventer, the packing seal device, and the rubber seal device are connected by threads. The blowout preventer is provided with a trapezoidal oil receiving groove (2). The blowout preventer includes a blowout preventer cap (34) surrounding the polished rod (1). The blowout preventer cap (34) is provided with a slide (35). A blowout preventer ball (31) is installed in the slide (35). A spring (32) that can push the blowout preventer ball (31) inward is provided in the blowout preventer cap (34). A baffle is installed on one side of the spring (32) to push the blowout preventer ball. The diameter of the blowout preventer ball (31) is larger than the diameter of the polished rod (1).

2. The wellhead blowout preventer polished rod seal as described in claim 1, characterized in that: The packing sealing device includes a ball head fastening sleeve (54) surrounding the polished rod (1), a ball head assembly (53) installed inside the ball head fastening sleeve (54), the bottom of the ball head assembly (53) including a rotatable universal ball head and a sealing tube located at the upper end of the universal ball head, the top of the ball head assembly (53) being threadedly connected to the blowout preventer cap (34), the ball head assembly (53) having a hollow structure inside, the ball head assembly (53) having an annular groove, packing (52) installed inside the annular groove, and a barrier (51) for sealing the packing (52) installed above the packing (52).

3. The wellhead blowout preventer polished rod seal as described in claim 1, characterized in that: The rubber sealing device includes a push-pull rod fixing cap (64) arranged around the light rod (1), and the push-pull rod fixing cap (64) is equipped with a rubber (61) surrounding the light rod (1). The push-pull rod fixing cap (64) is provided with two cylinders (65) extending radially outward. The two cylinders (65) are symmetrically arranged. A push block (62) that can move along the cylinder (65) is installed inside the cylinder (65). After the push block (62) moves, it can squeeze the rubber (61).

4. The wellhead blowout preventer polished rod seal as described in claim 3, characterized in that: The outer end of the push block (62) is fixed with a push rod, which passes through the outer end face of the cylinder (65). The outer end of the push rod is connected to a semi-straight handle (63) that can drive the push rod to move.

5. The wellhead blowout preventer polished rod seal as described in claim 1, characterized in that: The outside of the blowout preventer cap (34) is provided with a pipe wrench force groove (4).

6. The wellhead blowout preventer polished rod seal as described in claim 2, characterized in that: The omnidirectional ball joint is an elliptical ball.

7. The wellhead blowout preventer polished rod seal as described in claim 1, characterized in that: The packing (52) is made of fluororubber.

Images